1. Acting like a complete douchebag in a way only possible on Facebook. This might involve relatively innocuous things like Facebook stalking or being a Facebook whore, or it might be a little more obnoxious, like telling Friend A that you can't go out on Saturday night and then posting tons of pictures from Friend B's party the next morning.

2. The innate quality of Facebook that inspires this sort of behavior.

"Why does his ex-girlfriend keep writing cute little posts on his wall? Do you think they've still got something going on?"